Pachygone ovata (Poir.) Miers ex Hook.f. & Thomson

Menispermaceae

Roxburgh, W. in Carey, W. (ed.) (1855) Flora Indica 1: 203.

Vine stem diameters to 10 cm recorded. Living bark layer very thin. Narrow concentric rings of included bark visible in transverse sections of the stem. 'Growth rings' visible in the bark.

Leaf blades +/- papery, about 4-15 x 2-9 cm, petioles about 1.2-6.5 cm long, very thin, about 1 mm diam. Upper and lower leaf blade surfaces often clothed in pale hairs. Oak grain visible in the twigs.

Male flowers: Inflorescence about 5-15 cm long, consisting of a number of short racemes on a central axis. Sepals three + three in two whorls, the outer ones smaller, about 1 mm long, inner sepals much wider and about 2 mm long. Petals about 1.5 mm long, the base bilobed, the lobes clasping or enveloping the base of the staminal filament. Stamens five or six per flower, filaments about 1-1.5 mm long. Female flowers: Inflorescence a raceme. Sepals three + three in two whorls, the outer ones smaller, about 1-1.5 x 1 mm, inner sepals about 2 x 2 mm. Petals six, about 1.5 x 1 mm, basal auricles enveloping the base of the staminodes. Staminodes small, usually six. Carpels three, placed close together, stigma sessile at the apex of each carpel and projecting +/- at right angles to the axis of the carpel.

Fruits globose, slightly compressed laterally, about 6-7 mm diam. Style persistent, located close to the base of the fruit. Seeds (endocarps) about 5-6 x 5 mm, laterally compressed, outer surface somewhat sculptured. Embryo U-shaped. Cotyledons U-shaped, about 8-10 mm long. Radicle about 0.5-0.6 mm long. Endosperm scanty.

Cataphylls 1 or 2, produced before the first pair of true leaves. First pair of true leaves +/- cordate, apex acute, base cordate. Both the upper and lower surfaces of the leaf blades clothed in hairs. Margins usually with one large tooth or small lobe on each side. Pulvinus present on the petiole. At the tenth leaf stage: leaf blade cordate, about 9-10 x 5-6 cm, apex acuminate to apiculate, base cordate, midrib slightly raised on the upper surface. Terminal bud and stem clothed in brown hairs. Seed germination time 22 to 38 days.

Occurs in WA, NT, CYP, NEQ and CEQ. Altitudinal range from near sea level to 500 m. Grows in beach forest, monsoon forest and the drier more seasonal rain forests. Also occurs in Sri Lanka, SE Asia and Malesia.

Cissampelos ovata Poir., Encycl. Meth. Bot. 5: 10(1804), Type: Indes orientales, P. Sonnerat. Holo: P?. Pachygone ovata var. dasyphylla Miq., Annales Musei Botanici Lugduno-Batavi 4 : 87(1868), Type: Iava: HORSFIELD. Pachygone pubescens Benth., Flora Australiensis 1: 58(1863), Type: Queensland. Quail Island, Sept 1855, J. Flood. Holo: K. Iso: MEL. Cebatha pubescens (Benth.) Kuntze, Revisio Generum Plantarum 1: 9(1891). Tristichocalyx pubescens (Benth.) F.Muell., Fragmenta Phytographiae Australiae 4: 27(1863). Tinospora hullsii F.Muell., Fragmenta Phytographiae Australiae 5: 147(1866), Type: Northern Territory, Escape Cliffs, C. Hulls. Holo: MEL. Iso: BRI, K. Pachygone hullsii (F.Muell.) F.Muell., Fragmenta Phytographiae Australiae 9: 81(1875).